Oxidative dehydrogenation process

ABSTRACT

Compositions comprising Fe/P/Group IIIA components are effective as catalysts in processes to convert organic compounds to compounds having a greater degree of unsaturation.

United States Patent 11 1 Gichowski a a1.)

n11 3,870,764 Mar. 11, 1975 .Assignee:

OXIDATIVE DEHYDROGENATION PROCESS Inventors: Robert S. Gichowski, SanLuis I Obispo, Califi; Floyd E. Farha, Jr.,

I Bartlesville, Okla.

Phillips Petroleum Company, Bartlesville, Okla.

Filed: June 21, 1972 Appl. No.: 264,932

uQs. c1. 260/680 E, 252/437, 260/290 v,

Int. Cl. C07c 5/18 Field of Search 260/680 References Cited UNITEDSTATES PATENTS 3,409,697 1 H1968 Callahan et a1. 2 60/680 E Croce ctal... 2b0/(180E Grassclli et a] 260/(180 E Davison 260/680 E Croce ctal260/680 E Ripley 260/680 E Shiraishi et ul. 2610/4653 PrimaryExaminer-Paul M. Coughlan. Jr.

' ABSTRACT 10 Claims, N0 Drawings 1 OXIDATIVE DEHYDROGENATION PROCESSFIELD OF THE INVENTION The invention relates to compositions foundeffective as dehydrogenation catalysts. The invention further relates todehydrogenation processes utilizing the compositions as catalysts. I

BACKGROUND or THE INVENTION A variety of compositions useful foremployment as catalysts in dehydrogenation processes are known. However,the search for better, more effective, catalyst compositions,preparations, and processes of utilization continues.

OBJECTS OF THE INVENTION It is an object of our invention to providenovel compositions useful as catalysts. It is a further object of ourinvention to provide effective yields of desired products throughdehydrogenation processes.

Other aspects, objects, and several advantages of our invention willbecome apparent to those skilled in the arts to which our invention mostnearly appertains upon consideration of our disclosure as presented inthis specification further including the appended claims.

SUMMARY OF THEINVENTION According to our invention, novel compositionsare provided which comprise Fe/P/Group IIIA metal promoted with (III) aGroup IIIA metal component. One or more of the elements in thecomposition can be combined with oxygen.

These compositions, employed as catalysts, exhibit effective propertiesand abilities to convert, for exam pie, 2! paraffin to an olefin, suchas a butane to butene, or to convert a monoolefin to a diene, such as anisoamylene to isoprene or a butene to butadiene. These and otherdehydrogenation conversions are valuable processes for the conversion oforganic materials into other, frequently less plentiful or available andtherefore 'more valuable, organic compounds.

DETAILED DESCRIPTION OF THE INVENTION I Compositions The compositions ofour invention comprise (I) an iron component, (II) a phosphoruscomponent, promoted by (Ill) a Group IIIA-component, more particularlyone or more of boron, aluminum, gallium, indium, or thallium. One ormore of such components can be combined with oxygen in the compositions.A presently preferred preparation is by calcining an admixture of thecomponent-containing compounds in a molecular oxygen-containingatmosphere.

In our compositions as catalysts according to one as pect of ourinvention, the relative amounts of each component can vary widely, solong as there is an effective relationship in the final compositionproduced, i.e., each component is present in a sufficient weightrelationship of one to the other so as to provide catalyticeffectiveness of the composition combination.

Of course, any particular composition component need not necessarily bepresent in the elemental state, but can be present in a combined formwith one or more other elements. Neither the valence state not theelemental state, combined or uncombined state, is considered critical inour invention, and the exact nature v as to combined or uncombined form,oxidative or reduced state, of any particular component'or constituentsin the compositions of our invention, is not to be limitative of ourinvention, since it is not at present possible to particularly definethe exact chemical state of any particular component. i

Presently preferred for most catalytic purposes are compositions inwhich iron represents about 15 to 45 weight per cent, phosphorus about15 to 40 weight per Cent, and Group IIIA metal about 0.1 to 10 weightper cent, of the total composition. Thetotal per cent values of] plus IIplus III need not total 100. Oxygen can be present in a combined formwith one or more other components sufficient to satisy the unsatisfiedvalences thereof. Each component of our compositions is calculated asthe element itself.

Two or more Group IIIA metal components can be utilized for ourcompositions, and where such are employed, the total thereof is thatreflected in the group component weight relationships expressed.

It presently is preferred, for conversion and selectivity, that thecatalytic compositions of our invention reflect a range of about 20 to35 weight per cent iron, about 20 to 30 weight per cent phosphoruscomponent, and about 1 to 5 weight per cent for the Group IIIAcomponent, each component again expressive of the elementitself,although not indicating that such component is necessarily present asthe element itself.

A preferred group of catalytic compositions for conversion andselectivity, are aluminum or gallium Fe/P/O compositions.

A preferred group of catalysts at present, for selectivity andconversion, are Group IIIA metal-promoted calcined Fe/P/O' compositionswhich contain phosphorus in an amount greater than thatstoichiometrically required for simple iron phosphates. The amountofphosphorus present is in excess of the stoichiometric amount requiredfor the phosphorus to react in the form of phosphate as PO," ions withall of the iron in the iron reagent used to prepare the catalystcomposition. The amount of such excess phosphorus should be in a rangeof about 1.01 to 5, more preferably about 1.01 to 2, times thestoichiometric amount for iron orthophosphate. These stoichiometricphosphorus contents vary, of course, according to the valence of theiron in the iron compound. Thus, for best results, more than 0.67 mole,preferably more than one mole, of phosphorus is present for each mole ofiron.

Particularly effective, we have found, are Alor Gapromoted Fe/P/Ocatalyst compositions wherein the P is excess of the stoichiometricamount required as P0,, for the present according to the valence stateof the iron to the extent of 1.0] to 5 times the stoichiometric amount.

Catalyst Preparation The (I) iron component broadly can be derived fromelemental iron or from any iron containing compounds as a class,including the presently preferred oxides or compounds convertible to theoxides on drying or calcining, such as the hydroxides or nitrates; aswell as the The (ll) phosphorus component can be derived from elementalphosphorus or from any compound or mixtures of compounds of phosphorus,presently preferred being the oxides or compounds convertible thereto ondrying or calcining.

The (W) Group lllA metal component can be derived from any of therespective elements or from compounds or mixtures of compounds of boron,aluminum, gallium, indium, or thallium, such as boron oxide, aluminumoxide, gallium phosphate. indium phosphate, thallium phosphate, thenitrates, carboxylate, sulfates, or the like, presently preferred beingthe oxides or compounds convertible thereto on drying or calcining.

Double salts or compounds can be employed where desired, or compoundscontaining components from two or more groups can be utilized, such asaluminum phosphate, or iron phosphate, or the like, such that theresulting composition contains the desired components as we havedescribed.

Relatively minor amounts of other element may be present as traceconstituents in compounds or component-containing materials beingemployed, or present in a combined form not completely eliminated ondrying and/or calcining. The presence of such is not unacceptable solong as not detrimental in a sufficient degree as to interfere in theeffectiveness ofour compositions as catalysts. For example, ammonium oralkali metal or alkaline earth metal hydroxides may be used in apreparation procedure such as precipitation. Small residual amounts ofthe alkali or alkaline earth metal hydroxides are not objectionable inthe final compositions. Similarly, if iron sulfate or a Group lIlA metalsulfate is employed in the preparation, small residual amounts ofcombined sulfur can be tolerated. Halogen residues, on the other hand,presently are considered undesirable and should be minimized.

Our compositions and catalysts can be prepared by any method suitablewhich will result in the described compositions. Suitable methodsinclude coprecipitation from aqueous or organic or combinationsolution-dispersions or suspensions, impregnation, dry mixing, or thelike, alone or in various combinations. in general, any method can beutilized which provides effective amounts of the prescribed componentsin effective proportions. It is presently preferred that the finalcompositions, where they are to be employed as catalysts, have asufficiently high surface area so as to permit most effective catalyticoperation, such as about 1 square meter or more per gram.

One suitable and illustrative method of composition preparation involvesadmixing finely divided elements or one or more compounds such that theadmixture contains the necessary components. The components can beadmixed in the dry state, although adding sufficient water or otherconvenient diluent or slurryforming liquid or suspension-formingmaterial so as to make a workable slurry, and then intimately admixingusually is more convenient.

Where a slurry is prepared, the liquid components are removed such as bydrying using vacuum or heat or combinations to form a dried composite,usually employing a temperature sufficient to volatilize the water orthe diluents, such as from about 220 to 450 F., although lessertemperatures can be used under vacuum conditions.

elevated temperature, which can be at any convenient suitablecalcination range, such as about 900 to l,800

"F., or more, more usually from about l,000 to l,400

F., over a time suitable or convenient, such as up to 24 hours more-orless. The calcination step also provides activation of the compositionsas catalysts. The activation-calcination step preferably includesexposure of the composite to a molecular oxygen-containing gas such asair, or oxygen diluted with some other component such as carbon dioxide,or steam, or other combination.

In preparation of one of the preferred catalysts of our invention, andiron/phosphorus/oxygen composition can be prepared by treating an ironoxide, or other compound such as iron hydroxide, any ofthe ironphosphates, or other suitable iron salt, with phosphoric acid.Alternatively, an iron compound can be dry mixed with such asphosphorous pentoxide, or the like, or. iron phosphates can beprecipitated under conditions such that the precipitate contains thedesired amount of phosphorus, preferably in excess of that required tocombine with all of the iron in the form of orthophosphate. Theresulting Fe/P/O composition, either before or after thecalcination-activation step, can be impregnated conveniently withaqueous or nonaqueous solutions or dispersions of one or more Group lllAmetal compounds convertible to the oxide or substantially convertible tothe oxide on calcination. For example, an excess-phosphorus Fe/P/Ocomposite can be impregnated with an aqueous solution of aluminumnitrate. The impregnated composite is dried, and calcined in air. Thebase Fe/P/O composite can be initially calcined, then impregnated, andthen activated by calcining. Or, the base composite can be simply a drycomposite, the Group lIIA component added, and the entire composite thensubjected to the activationcalcination step.

In an alternative method of catalyst preparation, solutions ordispersions of iron componentand Group IIIA metal component-containingcompounds can be coprecipitated by the addition of an ammonium or analkali metal or alkaline earth metal hydroxide. The precipitate obtainedthen is separated, washed, dried, and the resulting solid impregnatedwith a solution of a phosphorus containing compound such as phosphoricacid. Such a composite then is activated by calcination.

in preparation of low density porous catalyst compositions, a solutionor dispersion containing compounds of iron, phosphorus, and Group lllAmetal component can be heated, with or without vacuum, until sufficientwater has been removed that the admixture becomes, with continuedapplication of heat, a hot viscous syrupy liquid. This substantiallymolecularly dehydrated admixture then subjected to a relatively rapidheating rate to raise the temperature to a relatively high range, suchas to about 1,000 to l,400 F. or more over an interval not exceedingabout 4 hours, preferably not exceeding about 2 hours. Relative rapidheating to the calcination temperature range effects a foaming andexpansion of the liquid mixture, and then ultimately solidification to aporous uniform mass having low apparent density. After reaching thecalcination temperature, the mass is further heated in air or molecularoxygen containing gas at a calcination temperature for final activationas catalyst.

The compositions can be formed into any convenient shape or structurefor utilization, depending on the particular purpose or use to whichthey may be put, type of reactor or contactor, and the like. Thecompositions can be prepared in the form of tablets, extrudates, finelydivided powders, agglomerates, and the like, by various methods. Forconvenience in shaping, such particle-forming steps usually should beconducted prior to the calcination-activation step. Where desired, thecomposition subsequently to calcination-activation can be ground, andthe ground composite compacted into form and density suitable forultimate contacting and employment.

The compositions as catalysts can be prepared with or without a support.Where desired for strength, or for catalyst distribution or dilution invarious types of reactors and for various feedstock contacting purposes,a variety of catalyst supports can be utilized including such as silica,boria, titania, zirconia, magnesia, singly, in admixture, or incombination such as silica-alumina, and the like. When a support isutilized, the aforementioned weight ratios of one component to the otherare exclusive of any such support material. Dehydrogenation FeedstocksOrganic feedstocks for which our compositions can be employed ascatalysts in oxidative dehydrogenation processes are those feedstreamsor feedstocks containing one or more dehydrogenatable organic compoundsalone or in admixture, or in diluted form with nondehydrogenatablematerial such as steam, nitrogen, and the like.

Dehydrogenatable organic compounds can be characterized as containing atleast one grouping. Compounds to be so dehydrogenated typically containin the range of 2 to 12 carbon atoms per molecule. it is feasible todehydrogenate compounds of a dehydrogenatable character containing agreater number of carbon atoms, although such are not often readilycommercially available. More specifically, the upper carbon limitationmentioned does not indicate limitation on the effectiveness of ourcompositions where employed as catalysts, nor of processes employing ourcompositions, but only refers to suggested more available feedstocks.Compounds to be dehydrogenated can be of branched or unbranchedstructure.

Particularly suitable for processes employing our compositions ascatalysts are the hydrocarbons, including cyclic and acyclic as well,more particularly the acyclic. Particularly desired for dehydrogenatablefeedstocks employing our compositions as catalysts are thedehydrogenatable acyclic monoolefins such as lolefins or 2olefins,although other monoolefins also can be successfully dehydrogenated to ahigher degree of unsaturation. Dehydrogenatable alkenes can beconverted, particularly those having from 3 to 12, presently preferably4 to 6, carbon atoms per molecule, and the cycloalkenes containing from4 to l0, preferably 4 to 6, carbon atoms per molecule, which can beconverted to the corresponding alkadienes and cycloalkadienes.

In addition, alkylpyridines and alkyl aromatic compounds containing from1 to 4, preferably 1 to 2, alkyl groups per molecule wherein the alkylgroups themselves contain from 1 to 6, preferably 2 to 6, carbon atomsper group and including at least one alkyl group having a minimum of 2carbon atoms, can be converted to the corresponding alkenyl-substitutedpyridines and alkenyl-substituted aromatic compounds.

Feedstocks utilized can be relatively pure feedstocks, i.e., a singlecompound; or can be employed as mixed feedstocks available from variousrefinery streams and containing a variety of components dehydrogenatableor some merely diluent in the sense of not being dehydrogenatable.

The conversions of isoamylenes to isoprene, butenes to butadiene,ethylbenzene to styrene, and 2-methyl-5- ethylpyridine to2methyl-5-vinylpyridine, presently are considered most advantageous.Representative feedstocks or feedstock components include ethane,2,4-dimethyloctane, Z-methylbutene-l, hexene-Z, octene-l,3-methylnonene-4, dodecene-l, propylene, nbutenes, n-pentenes,isopentenes, cyclobutene, cyclopentene, cyclohexene,3-isobutylcyclopentene, ethylbenzene, propylbenzene, isobutylbenzene,l-methyl-Z- propylbenzene, l-butyl-3-hexylbenzene, ethylpyridine.2-methyl-5-ethyl pyridine, 2,3,4-triethylmethyl-S-ethyl pyridine,27ethyl-5-hexyl pyridine, and the like.

In the course of oxidative dehydrogenation processes some amounts,generally small amounts, of oxygenated products also may be formed.These products may include such as furan, aldehydes such as acetaldehydefrom the conversion of butenes, and the like. Other compounds such asfurfural, or even acids such as acetic acid, may be obtained. Carbonoxides and water also may be formed either by chemical reactions, or, inthe case of water also by condensation of the steam during recovery ofthe products.

In another embodiment of oxidative processes employing our compositionsas catalysts, dehydrogenatable feedstocks of the cyclic and acyclicalkadienes of 4 to 12 carbon atoms, per molecule although compounds ofgreater number of carbon atoms are useful, preferably of4 to 6 carbonatoms, can be employed to produce a variety of oxygenated products suchas ethers, aldehydes, acids, and the like. The diene feedstocks, such asbutadiene, octadiene, and the like, can correspond to any of themonoolefin compounds already exemplified, simply adding the furtherdouble bond, without needlessly repeating a list of exemplary compounds.Dehydrogenation Conditions In a dehydrogenation process, the feedstock,together with a molecular-oxygen containing gas, optionally preferablyfurther with steam, is form into admixture, preferably preheated, andthen contacted with our compositions as catalysts.

Any contacting method or reactor suitable for the oxidativedehydrogenation arts can be employed, such as the presently preferredfixed contacting catalyst beds, as a single bed, as a graded series ofbeds of differing degree of catalyst activity or of contactingtemperatures, or by any other contacting method or approach such asfluidized beds, and the like.

Hydrocarbon feedstocks to be dehydrogenated according to the process ofour invention can be contacted at contacting temperatures over a broadrange, utilizing any contacting pressures and feed rates,oxygenthydrocarbon ratios, hydrocarbonzsteam ratios, employed in thedehydrogenation arts and suitable for the degree or extent of conversiondesired within contacting times to be employed.

Suggested contacting conditions include temperatures in the range ofabout 800 to 1300 F., presently preferably 900 to ll F.; contactingpressures of about 0.05 to 250 psia, presently preferably about 0.1 to25 .psia; oxygenzfeed ratios of about 01:1 to 3:1, presently preferablyabout 0.5:1 to 2:1, volumes of oxygen per volume of feed; steamzfeedratios of about O.l:l to l00:l, presently preferably about :1 to :1,volumes of steam per volume of feed; gaseous hourly space velocity GHSVof about 50 to 5000, presently preferably about 100 to 2,500, volumes oforganic feed vapor per volume of catalyst per hour.

The use of steam frequently is beneficial in dehydrogenation processesfor heat transfer purposes to assist in removing heat of reaction. Wheresteam is so employed, a steamzhydrocarbon ratio of up to about 100:] ormore can be utilized, although further dilutions presently appearunnecessary and wasteful of the steam.

Effluent from the reaction zone or zones can be subjected to anysuitable separation method so as to isolate and recover desired productor products, to separate unconverted or partially converted feed orcomponents for recycle to the contacting zone or for other use in themodern integrated chemical refinery or petrochemical processingoperation which more and more frequently is being termed apetrocomplexity.

Our compositions, employed under appropriate conditions as catalysts,have a long active life and seldom need, if ever, to undergoregeneration. However, should regeneration become indicated or isdesired, according to operational controls, or because of inactivationpossibly attributable to minor amounts of poisons, such as in thefeedstocks, or introduced inadvertently or for other causes, ourcatalyst compositions can be readily regenerated. Regeneration can beaccomplished by ceasing the flow of feedstock, continuing the flowofmolecular oxygen-containing gas, preferably also of steam in order tomaintain suitable temperatures, and otherwise maintaining operatingconditions of temperature and the like for a sufficient time to restoresubstantial activity to the catalyst compositions.

compounds such as the organo-substituted phosphines and the like can beused.

EXAMPLE The following data serve to illustrate the use of ourcompositions as catalysts. Particular components. species, conditionsemployed, are intended to be illustrative of our invention and not[imitative of the reasonable and proper scope thereof.

Al/Fe/P/O Catalyst A: 150 Ml of 1 molar Fe(NO were mixed with 20 ml of HPO (85 per cent), and 6 g of AI(NO .9H O. The resulting solution wasevaporated by heating with stirring until it became a sticky syrup. Thesyrup was transferred to a furnace and heated up to l200 F. over a2-hour period, and then calcined at l,200 F. for 4 additional hours. Theresulting composition was ground and screened to 20 to 28 mesh size. Thecatalyst contained 3 per cent Al, 25 per cent Fe, and 27 per cent P, byweight.

Fe/P/O Catalyst BzFor purposes of comparison, a similar but Al-freeFe/P/O catalyst was prepared containing 23 per cent Fe and 27 per centP, by weight.

Ga/Fe/P/O Catalyst C:9 G of Ga(NO .9H O were mixed with 7 ml of H PO,(85 per cent) and diluted to ml with water. The resulting solution wasmixed with 30 g of Fe (PO,) The mixture was dried and calcined 4 hoursat l,200 F. The catalyst contained 4.8 per cent Ga, 30 per cent Fe, and22 per cent P, by weight.

Fe/P/O Catalyst DzFor purposes of comparison, a similar but Ga-freeFe/P/O catalyst was prepared containing 30 per cent Fe and 22 per centP, by weight,

The catalysts prepared as described above were tested for activity in anoxidative dehydrogenation conversion of 2-methylbutene-2 (2-MB-2) toisoprene. A mixture of 2-methylbutene-2, steam, and air was passedthrough a fixed bed of each ofthe catalysts, The results, as well as theessential reaction conditions, are shown in Table l below.

TABLE I Oxidative Dehydrogenation of 2-Methylbutene-2 to lsoprene"Conversion expressed as moles of isoamylenes consumed per 100 molesZ-MB-Z fed. sampled after 36 hours on stream at I050 F. and atmosphericpressure.

"Modivity is a modified selectivity based on analysis of gas phaseproducts which include carbon oxides, cracked products, isuprene, andisoamylenes.

Yield expressed as moles of isoprenc per I00 moles Z-MB-Z convened.

Over prolonged intervals of service, in some instances, some of thephosphorus may tend to dissipate from the catalyst compositions.Consequently, to maintain such catalyst at a suitably high level ofactivity, a small effective quantity of a phosphorus-containing compoundcan be intermittently or continuously introduced into the reaction zone,conveniently during operational intervals. The level of phosphorusaddition can correspond to the level of phosphorus loss, which lattercan be readily determined by analysis of reactor effluent, particularlyanalysis of steam condensate. Any suitable phosphorus compound can beemployed such as any of the phosphoric acids, phosphorus oxides such asphosphorus pentoxide, as well as organophosphorus The data in Table Iabove illustrate the beneficial regrouping under oxidativedehydrogenation conditions including the presence of molecular oxygenwith a catalyst composition comprising (1) iron, (11) phosphorus, (lll)gallium, and (1V) oxygen, sulfur, or oxygen and sulfur, each of said(1), (11), (111), and (1V), calculated as the element, present in aratio sufficient to provide catalytic effectiveness, wherein saidcatalyst composition contains about to 45 weight percent said (1), about15 to 40 weight percent said (11), and about 0.1 to 10 weight percentsaid ([11),

wherein said dehydrogenatable organic compound comprises an acyclichydrocarbon monoolefin of 3 to 12 carbon atoms per molecule, cyclichydrocarbon alkenes of4 to 10 carbon atoms per molecule, alkylpyridinesor alkylaromatics containing 1 to 4 alkyl groups per molecule whereinthe alkyl group contains 1 to 6 carbon atoms per group such that atleast 1 alkyl group has at least 2 carbon atoms, and cyclic or acyclicalkadienes of 4 to 12 carbon atoms per molecule.

2. The process according to claim 1 wherein said acy clic monoolefincontains 4 to 6 carbon atoms per molecule, said cyclic alkenes contain 4to 6 carbon atoms per molecule, said alkylpyridines or alkylaromaticscontain 1 to 2 alkyl groups per molecule, and said cyclic. or acyclicalkadienes contain 4 to 6 carbon atoms per molecule.

3. The process according to claim 1 wherein said process further employssteam.

4. The process according to claim 3 wherein said oxidativedehydrogenation conditions include contacting temperature of about 800to 1300 F.; contacting pressure of about 0.05 to 250 psia; oxygenzfeedratio of about 0.1:] to 3:1 volumes of oxygen per volume of feed;steamzfeed ratio of about 0.1:1 to 100:1 volumes of steam per volume offeed; and a GHSV of about 50 to 5,000 volumes of organic feed vapor pervolume of catalyst per hour.

5. The process according to claim 4 further employing a small effectiveamount of at least one phosphoruscontaining compound sufficient tosubstantially maintain catalyst activity.

6. The process according to claim 4 wherein said dehydrogenatablehydrocarbon is 2-methylbutene-2.

7. The process according to claim 1 wherein said catalyst compositioncomprises about 20 to weight percent said (I), about 20 to 30 weightpercent said (11), and about 1 to 5 weight percent said (111).

8. The process according to claim 1 wherein the amount of said (11)phosphorus present represents about 1.01 to about 5 times the amount ofphosphorus necessary to combine with said (I) iron as theorthophosphate.

9. An oxidative dehydrogenation process which comprises contacting atleast one dehydrogenatable organic grouping under oxidativedehydrogenation conditions including the presence of molecular oxygenwith a catalyst composition consisting essentially of (1) iron, (11)phosphorus, (111) gallium, and (1V) oxygen, sulfur, or oxygen andsulfur, each of said (1), (11), (111), and (1V), calculated as theelement, present in a ratio sufficient to provide catalyticeffectiveness including about 0.1 to 10 weight percent said (111)gallium, thereby dehydrogenating said compound to a higher degree ofunsatu ratlon,

wherein said dehydrogenatable organic compound comprises an acyclichydrocarbon monoolefin of 3 to 12 carbon atoms per molecule. cyclichydrocarbon alkenes of4 to 10 carbon atoms per molecule. alkylpyridinesor alkylaromatics containing 1 to 4 alkyl groups per molecule whereinthe alkyl group contains 1 to 6 carbon atoms per group such that atleast 1 alkyl group has at least 2 carbon atoms and cyclic or acyclicalkadienes of 4 to 12 carbon atoms per molecule. 10. An oxidativedehydrogenation process which comprises contacting at least onedehydrogenatable or-- ganic compound containing at least one groupingunder oxidative dehydrogenation conditions including the presence ofmolecular oxygen with a catalyst composition comprising (1) iron, (11)phosphorus, (III) gallium, and (IV) oxygen, sulfur, or oxygen andsulfur, wherein each of said (1), (11), (111), and (1V), calculated asthe element, is present in a ratio sufficient to provide catalyticeffectiveness including about 0.1 to 10 weight percent said (Ill)gallium, and wherein the amount of said ([1) phosphorus presentrepresents about 1.01 to about 5 times the amount of phosphorusnecessary to combine the said (1) iron as the orthophosphate, therebydehydrogenating said dehydrogenatable organic compound to a higherdegree of unsaturation,

wherein said dehydrogenatable organic compound comprises an acyclichydrocarbon monoolefin of 3 to 12 carbon atoms per molecule, cyclichydrocarbon alkenes of 4 to 10 carbon atoms per molecule, alkylpyridinesor alkylaromatics containing 1 to 4 alkyl groups per molecule whereinthe alkyl group contains 1 to 6 carbon atoms per group such that atleast 1 alkyl group has at least 2 carbon atoms, and cyclic or acyclicalkadienes of 4 to 12 carbon atoms per molecule.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTIONPATENT NO. 3,870,76h

DATED 1 March 11, 1975 |NVENTOR(S) Robert S. Cichowski et 8.1

It rs certified that error appears in the Zlb0V6--!d9|]tift8d patent andthat said Letters Patent are hereby corrected as shown below:

Cover page, lines 2 and 5, "Gichowski" should be Cichowski Signed andSealed this eleventh D 21-) O f November 1 9 75 [SE/\L A lies I:

RUTH C. MASON C. MA-RSHALL DANN (mnmr'xxinm-r 1! Patent; uml I'rmlvmurkx

1. AN OXIDATIVE DEHYDROGENATION PROCESS WHICH COMPRISES CONTACTING ATLEAST ONE DEHYDROGENATABLE ORGANIC COMPOUND CONTAINING AT LEAST ONE 1.An oxidAtive dehydrogenation process which comprises contacting at leastone dehydrogenatable organic compound containing at least one
 2. Theprocess according to claim 1 wherein said acyclic monoolefin contains 4to 6 carbon atoms per molecule, said cyclic alkenes contain 4 to 6carbon atoms per molecule, said alkylpyridines or alkylaromatics contain1 to 2 alkyl groups per molecule, and said cyclic or acyclic alkadienescontain 4 to 6 carbon atoms per molecule.
 3. The process according toclaim 1 wherein said process further employs steam.
 4. The processaccording to claim 3 wherein said oxidative dehydrogenation conditionsinclude contacting temperature of about 800* to 1300* F.; contactingpressure of about 0.05 to 250 psia; oxygen:feed ratio of about 0.1:1 to3:1 volumes of oxygen per volume of feed; steam:feed ratio of about0.1:1 to 100:1 volumes of steam per volume of feed; and a GHSV of about50 to 5, 000 volumes of organic feed vapor per volume of catalyst perhour.
 5. The process according to claim 4 further employing a smalleffective amount of at least one phosphorus-containing compoundsufficient to substantially maintain catalyst activity.
 6. The processaccording to claim 4 wherein said dehydrogenatable hydrocarbon is2-methylbutene-2.
 7. The process according to claim 1 wherein saidcatalyst composition comprises about 20 to 35 weight percent said (I),about 20 to 30 weight percent said (II), and about 1 to 5 weight percentsaid (III).
 8. The process according to claim 1 wherein the amount ofsaid (II) phosphorus present represents about 1.01 to about 5 times theamount of phosphorus necessary to combine with said (I) iron as theorthophosphate.
 9. An oxidative dehydrogenation process which comprisescontacting at least one dehydrogenatable organic compound containing atleast one